Low progesterone level? HELP

So I went in for a CD 21 blood draw after first round clomid 50mg (I was 5DPO) and I got my results today. It was 4.9 and they told me that was good and that it shows I did ovulate but I've been doing some reading (stressing myself) and that seems kinda low. Anybody care to give some input or any opinion? ANYTHING WOULD HELP.